Preminary analysis of performance of avionics equipment using worst case analysis
천영호 Young-ho Cheon , 우희승 Hui-seung Woo , 서인범 Inn-beom Seo , 안태식 Tae-sik Ahn
26(4) 185-194, 2022
천영호 Young-ho Cheon , 우희승 Hui-seung Woo , 서인범 Inn-beom Seo , 안태식 Tae-sik Ahn
DOI: JANT Vol.26(No.4) 185-194, 2022
Avionics equipment requires various environmental conditions and performance during development, and as a countermeasure against such development risk, the worst-case circuit analysis(WCCA) is applied to predict perform preliminary performance analysis. WCCA calculates the maximum and minimum values by combining the parameter values of the relevant circuit after deriving the parameter values in consideration of the aging of the temperature and operating period at the component level. In this paper, the necessary matters for WCCA application are described. Chapter 2 describes the differences and characteristics of the WCCA techniques EVA, RSS, and Monte Carlo.Chapter 3 introduces the analysis process through the example circuit to introduce the actual analysis procedure. Chapter 4 describes the method of selecting an analysis technique for each condition of the analysis target. As a result of applying the procedures and analysis methods introduced in this paper when open, it was confirmed that preliminary performance analysis and part optimization design verification are possible.
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Error Model Analysis and Performance Evaluation for the Rapid Alignment Technique of Projectile Navigation System in Inclined Launch Systems
박세빈 Sebeen Park
26(4) 195-204, 2022
박세빈 Sebeen Park
DOI: JANT Vol.26(No.4) 195-204, 2022
In this paper, we described the rapid initial alignment techniques of projectile navigation system for use in inclined launch systems. One-shot alignment technique, one of the rapid initial alignment techniques, is possible to align a navigation system within seconds because it uses external information from an launcher navigation system. However, since it has only been used in vertical launch systems, its performance in inclined launch systems has not been verified. Therefore, this paper analyzed the error elements that occur when the one-shot alignment technique is applied to the inclined launch system, and introduced a method to improve the alignment performance by minimizing those errors. Additionally, By simulating and testing the performance of the proposed alignment technique, it was verified that it is effective even in an environment where a real navigation system is used.
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A Proposal for Software Framework of Intelligent Drones Performing Autonomous Missions
신주철 Ju-chul Shin , 김성우 Seong-woo Kim , 백경훈 Gyong-hoon Baek , 서민기 Min-gi Seo
26(4) 205-210, 2022
신주철 Ju-chul Shin , 김성우 Seong-woo Kim , 백경훈 Gyong-hoon Baek , 서민기 Min-gi Seo
DOI: JANT Vol.26(No.4) 205-210, 2022
Drones, which have rapidly grown along with the 4th industrial revolution, spread over industries and also widely used for military purposes. In recent wars in Europe, drones are being evaluated as a game changer on the battlefield, and their importance for military use is being highlighted. The Republic of Korea Army also planned drone-bot systems including various drones suitable for echelons and missions of the military as future defense forces. The keyword of these drone-bot systems is autonomy by artificial intelligence. In addition, common use of operating platforms is required for the rapid development of various types of drones. In this paper, we propose software framework that applies diverse artificial intelligence technologies such as multi-agent system, cognitive architecture and knowledge-based context reasoning for mission autonomy and common use of military drones.
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Design and Implementation of BNN based Human Identification and Motion Classification System Using CW Radar
김경민 Kyeong-min Kim , 김성진 Seong-jin Kim , 남궁호정 Ho-jung Namkoong , 정윤호 Yun-ho Jung
26(4) 211-218, 2022
김경민 Kyeong-min Kim , 김성진 Seong-jin Kim , 남궁호정 Ho-jung Namkoong , 정윤호 Yun-ho Jung
DOI: JANT Vol.26(No.4) 211-218, 2022
Continuous wave (CW) radar has the advantage of reliability and accuracy compared to other sensors such as camera and lidar. In addition, binarized neural network (BNN) has a characteristic that dramatically reduces memory usage and complexity compared to other deep learning networks. Therefore, this paper proposes binarized neural network based human identification and motion classification system using CW radar. After receiving a signal from CW radar, a spectrogram is generated through a short-time Fourier transform (STFT). Based on this spectrogram, we propose an algorithm that detects whether a person approaches a radar. Also, we designed an optimized BNN model that can support the accuracy of 90.0% for human identification and 98.3% for motion classification. In order to accelerate BNN operation, we designed BNN hardware accelerator on field programmable gate array (FPGA). The accelerator was implemented with 1,030 logics, 836 registers, and 334.904 Kbit block memory, and it was confirmed that the real-time operation was possible with a total calculation time of 6 ms from inference to transferring result.
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Connection Admission Control Using RA Based Dynamic Spectrum Hole Grouping in Multi-classes Cognitive Radio Networks
이진이 Jin-yi Lee
26(4) 219-225, 2022
이진이 Jin-yi Lee
DOI: JANT Vol.26(No.4) 219-225, 2022
In this paper, we propose a CAC exploring a RA based dynamic spectrum hole grouping for secondary users’ QoS enhancement in multi-classes cognitive radio networks. The RA based dynamic spectrum hole grouping uses SU multi-classes overlaying spectrum structure suggested here. Multiclass SUs are divided into real and nonreal, and real SUs have a priority for resource utilization against non real. The amount of resource required by real SUs is supported by Wiener prediction and the dynamic spectrum hole grouping, and that required by nonreal SU is supported by the remained available amount without prediction. In the simulations, we compare the proposed CAC performances using the dynamic spectrum hole grouping in terms of SU connection’s blocking(dropping) rate and resource utilization efficiency according to multi-classes traffic characteristics, and then we show the proposed CAC can guarantee the desired QoS of multi-classes secondary users.
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A slide reinforcement learning for the consensus of a multi-agents system
양장훈 Janghoon Yang
26(4) 226-234, 2022
양장훈 Janghoon Yang
DOI: JANT Vol.26(No.4) 226-234, 2022
With advances in autonomous vehicles and networked control, there is a growing interest in the consensus control of a multi-agents system to control multi-agents with distributed control beyond the control of a single agent. Since consensus control is a distributed control, it is bound to have delay in a practical system. In addition, it is often difficult to have a very accurate mathematical model for a system. Even though a reinforcement learning (RL) method was developed to deal with these issues, it often experiences slow convergence in the presence of large uncertainties. Thus, we propose a slide RL which combines the sliding mode control with RL to be robust to the uncertainties. The structure of a sliding mode control is introduced to the action in RL while an auxiliary sliding variable is included in the state information. Numerical simulation results show that the slide RL provides comparable performance to the model-based consensus control in the presence of unknown time-varying delay and disturbance while outperforming existing state-of-the-art RL-based consensus algorithms.
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An Analysis of the Attitude Estimation Errors Caused by the Deflection of Vertical in the Initial Alignment
김현석 Hyun-seok Kim , 박찬식 Chan-sik Park
26(4) 235-243, 2022
김현석 Hyun-seok Kim , 박찬식 Chan-sik Park
DOI: JANT Vol.26(No.4) 235-243, 2022
In this paper, in the case of an inertial navigation system, the posture estimation error in the initial alignment due to vertical deflection is analyzed. Posture estimation error due to DOV was theoretically analyzed based on the speed and posture error of INS. Simulations were performed to verify the theoretical grinding, and the results were in good agreement. For example, in the case of η = 20˝, an alignment error of φN =0.00287˚, φU =0.00196˚ occurred, and in the case of ζ=20˝, an error of φE = -0.00286˚ occurred. Through this, it was confirmed that the vertical posture error caused by the DOV occurred as a coupling characteristic of the INS posture error. It has been shown that an additional posture error may occur due to the DOV, which was not considered in the existing INS alignment, which means that correction for the DOV must be considered when applying high-precision INS.
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A Study on the Privacy Protection Trends and Policies of Korea · the U.S. · EU
조세홍 Sae-hong Cho
26(4) 244-248, 2022
조세홍 Sae-hong Cho
DOI: JANT Vol.26(No.4) 244-248, 2022
The various digital services that people are experiencing recently are bringing about changes in the daily lives, and these changes are due to the spread of the Fourth Industrial Revolution. The 4th Industrial Revolution is based on the development of ICT technology, and ICT technology inevitably generates issues such as the use and protection of personal information as well as the use of public data. Accordingly, countries around the world are making efforts to revitalize new industries by wisely solving conflicting issues between the use and protection of personal information through legislation. There are some differences in the protection and use of personal information in Korea, the United States, and the EU. Korea trys to make the legislation that prioritizes the use of data, and the United States establishes individual laws governing the protection of personal information by sector, while the EU has clarified the strengthening personal information protection. This paper aims to find out how personal information protection is defined in Korea, the United States, and the EU through enacted laws and organize the direction of the future policies.
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